1. Field of the Invention
This invention relates generally to digital data storage apparatus, and relates more particularly to an improved compact disc handling mechanism for transferring a compact disc to a cartridge for insertion into a player.
2. Description of the Relevant Art
One form of storing digital data is optically based, in which digital data is stored on and retrieved from a data disc in an optically discernible form using a laser read/write head. In use today are optically based disc systems for use as digital storage devices for computers. These storage devices are known as CD ROM devices, where "CD ROM" stands for compact disc read-only memory.
Some CD ROM devices house the disc in a cartridge for protection. When the cartridge is inserted into a disc player, the player loads the disc onto a spindle and rotates the disc so that a laser read/write head can access the data stored on the disc. One type of disc player includes an automatic loading mechanism that senses when the cartridge has been partially inserted into a slot in the player and then automatically moves the cartridge the rest of the way into the player. This type of player ejects a cartridge by moving the cartridge to the partially inserted position with about one inch of the cartridge protruding from the player.
Cartridge-based discs are fine for applications where only a few discs are needed and they can be loaded into the player manually. Where an automatic, multiple disc capability is desired, however, the larger size and added mass of the cartridge causes problems. Significantly more space is required to store discs in cartridges than is required for discs alone since the cartridges are larger than the discs themselves. The added mass of the cartridges is another problem since more force is required to move a group of cartridges than an equal number of discs alone.
It would be desireable to use a multiple disc changer apparatus for handling discs, such as those as disclosed in applicant's U.S. Pat. Nos. 4,750,160 and 4,815,057. There, discs without cartridges are stored on a round carousel and are loaded onto a player by a disc handling mechanism. A drawback to this type of changer is that cartridge-based players cannot be used without modification.